Search

Background: Lower birth weight is associated with diabetes although the underlying mechanisms are unclear. Muscle mass could be a modifiable link and hence a target of intervention. We assessed the associations of birth weight with muscle and fat mass observationally in a population with little socio-economic patterning of birth weight and using Mendelian randomization (MR) for validation. Methods: In the population-representative “Children of 1997” birth cohort (n = 8,327), we used multivariable linear regression to assess the adjusted associations of birth weight (kg) with muscle mass (kg) and body fat (%) at ~17.5 years. Genetically predicted birth weight (effect size) was applied to summary genetic associations with fat-free mass and fat mass (kg) from the UK Biobank (n = ~331,000) to obtain unconfounded estimates using inverse-variance weighting. Results: Observationally, birth weight was positively associated with muscle mass (3.29 kg per kg birth weight, 95% confidence interval (CI) 2.83 to 3.75) and body fat (1.09% per kg birth weight, 95% CI 0.54 to 1.65). Stronger associations with muscle mass were observed in boys than in girls (p for interaction 0.004). Using MR, birth weight was positively associated with fat-free mass (0.77 kg per birth weight z-score, 95% CI 0.22 to 1.33) and fat mass (0.58, 95% CI 0.01 to 1.15). No difference by sex was evident. Conclusion: Higher birth weight increasing muscle mass may be relevant to lower birth weight increasing the risk of diabetes and suggests post-natal muscle mass as a potential target of intervention. [ABSTRACT FROM AUTHOR]

Background: Men and women are increasingly likely to stay sexually active into later life, but research shows that sexual activity and satisfaction decrease with increasing age. Ill health and medical treatments may affect sexual activity but there is little research on why some older people with a health problem affecting their sexual activity are satisfied with their sex life, and others are not. Methods: A mixed method study integrating data and analyses from the third British National Survey of Sexual Attitudes and Lifestyles (n = 3343 aged 55–74 years) and from follow-up in-depth interviews with 23 survey participants who reported having a health condition or taking medication affecting their sex life. Results: Overall, 26.9% of men and 17.1% of women aged 55–74 reported having a health condition that affected their sex life. Among this group, women were less likely than men to be sexually active in the previous 6 months (54.3% vs 62.0%) but just as likely to be satisfied with their sex life (41.9% vs 42.1%). In follow-up interviews, participants sometimes struggled to tease out the effects of ill health from those of advancing age. Where effects of ill health were identified, they tended to operate through the inclination and capacity to be sexually active, the practical possibilities for doing so and the limits placed on forms of sexual expression. In close relationships partners worked to establish compensatory mechanisms, but in less close relationships ill health provided an excuse to stop sex or deterred attempts to resolve difficulties. Most fundamentally, ill health may influence whether individuals have a partner with whom to have sex. Conclusion: The data show complex interactions between health, lifestyle and relationship factors that affect sexual activity/satisfaction. When dealing with sexual problems in older people, practitioners need to take account of individual lifestyle, needs and preferences. [ABSTRACT FROM AUTHOR]

Objectives: To estimate the burden of intestinal infectious disease (IID) in the UK and determine whether disease burden estimations using a retrospective study design differ from those using a prospective study design. Design/Setting: A retrospective telephone survey undertaken in each of the four countries comprising the United Kingdom. Participants were randomly asked about illness either in the past 7 or 28 days. Participants: 14,813 individuals for all of whom we had a legible recording of their agreement to participate Outcomes: Self-reported IID, defined as loose stools or clinically significant vomiting lasting less than two weeks, in the absence of a known non-infectious cause. Results: The rate of self-reported IID varied substantially depending on whether asked for illness in the previous 7 or 28 days. After standardising for age and sex, and adjusting for the number of interviews completed each month and the relative size of each UK country, the estimated rate of IID in the 7-day recall group was 1,530 cases per 1,000 person-years (95% CI: 1135–2113), while in the 28-day recall group it was 533 cases per 1,000 person-years (95% CI: 377–778). There was no significant variation in rates between the four countries. Rates in this study were also higher than in a related prospective study undertaken at the same time. Conclusions: The estimated burden of disease from IID varied dramatically depending on study design. Retrospective studies of IID give higher estimates of disease burden than prospective studies. Of retrospective studies longer recall periods give lower estimated rates than studies with short recall periods. Caution needs to be exercised when comparing studies of self-reported IID as small changes in study design or case definition can markedly affect estimated rates. [ABSTRACT FROM AUTHOR]